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Coherent state transfer between an electron and nuclear spin in (15)N@C(60)
Richard M Brown1, Alexei M Tyryshkin, Kyriakos Porfyrakis
1Department of Materials, Oxford University, Oxford OX1 3PH, United Kingdom. richard.brown@materials.ox.ac.uk
Physical Review Letters
|April 8, 2011
Summary
This study introduces an electron-nuclear hybrid scheme for molecular qubits. It enables controllable coupling and leverages long nuclear spin coherence times for improved quantum information processing.
Area of Science:
- Quantum Computing
- Molecular Spintronics
- Quantum Information Science
Background:
- Electron spin qubits in molecular systems offer reproducibility and self-assembly.
- Neighboring electron spin qubits have 'always on' interactions.
- Electron spin coherence times are shorter than nuclear spin coherence times.
Purpose of the Study:
- To implement an electron-nuclear hybrid scheme for molecular qubits.
- To enable controllable interqubit coupling.
- To utilize long nuclear spin decoherence times.
Main Methods:
- Coherent spin transfer between electron and nuclear spins.
- Utilized (15)N nuclear spin in (15)N@C(60) molecule.
- Employed tuned microwave and radio frequency pulses.
Main Results:
- Achieved 88% two-way process fidelity for qubit state transfer.
- Demonstrated effective control over interqubit coupling.
- Measured a nuclear spin coherence lifetime exceeding 100 ms.
Conclusions:
- The electron-nuclear hybrid scheme effectively controls qubit coupling.
- Long nuclear spin coherence times significantly benefit quantum operations.
- This approach enhances the potential of molecular systems for quantum computing.
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